Abstract: An imager acquires a scene's image by pixels each of which has a digital storage device which accumulates information on a pertinent portion of the image. During image acquisition, the imager moves relative to the scene, and the contents of the digital storage devices are shifted from one pixel to another. In some embodiments, less than all bits of a digital storage device are shifted, and/or the shift is accompanied by some operation on the contents of the digital storage devices. Other features are also provided.

Abstract: A light-to-frequency converter includes a switch (130) connected in series with a reverse-biased photodiode (120). A node (150) in the current path through the switch and the photodiode is connected to the input of a Schmidt trigger (160), whose output controls the switch. New techniques are provided for motion compensation, partial readouts, dark current elimination, non-destructive testing, and sensing the state of a memory cell.

Abstract: A light-to-frequency converter includes a switch (130) connected in series with a reverse-biased photodiode (120). A node (150) in the current path through the switch and the photodiode is connected to the input of a Schmidt trigger (160), whose output controls the switch. New techniques are provided for motion compensation, partial readouts, dark current elimination, non-destructive testing, and sensing the state of a memory cell.

Abstract: A light-to-frequency converter includes a switch (130) connected in series with a reverse-biased photodiode (120). A node (150) in the current path through the switch and the photodiode is connected to the input of a Schmidt trigger (160), whose output controls the switch. New techniques are provided for motion compensation, partial readouts, dark current elimination, non-destructive testing, and sensing the state of a memory cell.

Abstract: Exemplary sigma-delta modulators include a summing block configured to receive an input signal, a noise shaping unit configured to process an output signal of the summing block, a quantizer configured to quantize an output signal of the noise shaping unit, and a current-mode digital-to-analog converter (“DAC”) configured to convert an output of the quantizer into an analog signal and input the analog signal into the summing block in a closed loop feedback manner.

Abstract: A pipelined analog-to-digital converter includes a plurality of stages, each stage comprising an analog-to-digital converter (ADC) and a digital-to-analog converter (DAC). A method for increasing the accuracy of the pipelined ADC includes calibrating the ADC in each stage of the analog-to-digital converter by adjusting trip points of that ADC. Another method for increasing the accuracy of a pipelined ADC includes measuring error in an output of each the DAC; and correcting an output of the pipelined analog-to-digital converter for the measured error. These methods can be used together to further increase the accuracy of the pipelined ADC. Consequently, a pipelined analog-to-digital converter may include a look-up table containing data for correcting errors in output of each of the DACs, where trip points of the ADCs the ADCs in the stages of the pipelined converter have been calibrated to expected values.

Abstract: A pipelined analog-to-digital converter includes a plurality of stages each including a sample-and-hold circuit configured to output an analog signal having a current and a current mode analog-to-digital converter configured to compare the current of the analog signal output by the sample-and-hold circuit to current generated by a plurality of current sources and output a digital representation of the analog signal.

Abstract: A current measuring system has an electrical component configured to provide an electrical current representative of a parameter of interest at an output node; and an analog to digital converter having a current input node in electrical communication with the output node of the electrical component.

Abstract: A light-to-frequency converter includes a switch (130) connected in series with a reverse-biased photodiode (120). A node (150) in the current path through the switch and the photodiode is connected to the input of a Schmidt trigger (160), whose output controls the switch. New techniques are provided for motion compensation, partial readouts, dark current elimination, non-destructive testing, and sensing the state of a memory cell.

Abstract: A method of converting an analog signal to a digital signal includes comparing an input current to one or more reference currents to generate the desired digital signal. An Analog-to-Digital Converter includes a plurality of current comparators; and a plurality of current references providing reference currents to the comparators.

Abstract: A system for emulating characteristics of a plurality of analog-to-digital converter (ADC) architectures in the conversion of an analog signal to a digital signal. The system comprises a flash ADC for sampling the analog signal and outputting a digital representation of a sample of the analog signal, a digital-to-analog converter (DAC) for supplying the reference values to the flash ADC, and a digital signal processor (DSP) for processing the digital representation of the sample and outputting the digital signal. The digital representation is based on a comparison of the sample to reference values and comprising a number of bits of resolution. The DSP is configured to send a modifiable control signal defining the reference values to the DAC.

Abstract: An analog-to-digital converter that does not use an external clock signal to convert an incoming analog signal to a digital output signal including two or more comparators configured to receive an analog input signal, a digital-to-analog converter configured to produce a reference signal for the comparators, and asynchronous logic configured to sample comparator results and adjust a digital output signal accordingly.

Abstract: A method and system by which multiple ADC architectures can be emulated comprises, a number of electrical components commonly used in a variety of ADC architectures, routing an analog input through a number of switches, and selectively connecting and disconnecting the switches to emulate one of multiple possible ADC architectures.

Abstract: A system for emulating characteristics of a plurality of analog-to-digital converter (ADC) architectures in the conversion of an analog signal to a digital signal. The system comprises a flash ADC for sampling the analog signal and outputting a digital representation of a sample of the analog signal, a digital-to-analog converter (DAC) for supplying the reference values to the flash ADC, and a digital signal processor (DSP) for processing the digital representation of the sample and outputting the digital signal. The digital representation is based on a comparison of the sample to reference values and comprising a number of bits of resolution. The DSP is configured to send a modifiable control signal defining the reference values to the DAC.

Abstract: An analog-to-digital converter that does not use an external clock signal to convert an incoming analog signal to a digital output signal including two or more comparators configured to receive an analog input signal, a digital-to-analog converter configured to produce a reference signal for the comparators, and asynchronous logic configured to sample comparator results and adjust a digital output signal accordingly.

Abstract: A method and system by which multiple ADC architectures can be emulated comprises, a number of electrical components commonly used in a variety of ADC architectures, routing an analog input through a number of switches, and selectively connecting and disconnecting the switches to emulate one of multiple possible ADC architectures.